The proposed research involves investigations of oxidation- reduction reactions of various biochemical cofactors that are encountered in biological oxidation-reduction processes. Our investigations are directed toward finding evidence of the intermediacy of free radicals in these reactions. Kinetic analysis of redox reactions involving the oxidation of ascorbic acid are under way that suggest that this reagent participates in free-radical chain processes. Other similar investigations are planned that involve other biochemical cofactors such as NADH, riboflavin and quinones. Effort is also directed toward studying the behavior of monohydropyridyl free-radicals with peroxide linkages. Work in this area will also be directed toward investigating the behavior of alpha- hydroxyalkyl radical and alpha-aminoalkyl radicals with peroxide linkages. Oxidations of formate esters in aprotic solvents are planned using the peroxydisulfate ion and the oxidizing agent. Longer range projects include electrochemical oxidation-reduction reactions of biological cofactors in aprotic media as well as investigations of model systems of the enzymes catalase and peroxidase.